排序方式： 共有75条查询结果，搜索用时 31 毫秒
21.
Marsilio F Di Martino B Di Francesco CE Meridiani I 《Veterinary research communications》2005,29(Z1):99-106
Ovine enzootic abortion is an infectious and contagious disease clinically characterized by abortion and weak neonates, affecting sheep and goats. The etiological agent is Chlamydophila (C.) abortus, which is considered one of the most common animal pathogens of small ruminants; it has important economic implications and represents a significant zoonotic risk. Clinical diagnosis is often difficult because the clinical signs and the pathological lesions are not specific for C. abortus infection, in fact they can also be observed as a result of infections with other abortifacient agents. Moreover, the involvement of the laboratory is necessary to perform the definitive diagnosis. One hundred and seventeen vaginal swabs from sheep with clinical signs related to chlamydial infection were examined by a PCR-RFLP assay that demonstrated high specifity and sensitivity. Six samples were positive for C. abortus. Vaginal swabs are easy to handle and allow to deal with biohazardous material in safety conditions. 相似文献
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Small-scale effects of historical land use and topography on post-cultural tree species composition in an Alpine valley in southern Switzerland 总被引：1，自引：0，他引：1
Investigations of spatial patterns in forest tree species composition are essential in the understanding of landscape dynamics,
especially in areas of land-use change. The specific environmental factors controlling the present patterns, however, vary
with the scale of observation. In this study we estimated abundance of adult trees and tree regeneration in a Southern Alpine
valley in Ticino, Switzerland. We hypothesized that, at the present scale, spatial pattern of post-cultural tree species does
not primarily depend on topographic features but responds instead to small-scale variation in historical land use. We used
multivariate regression trees to relate species abundances to environmental variables. Species matrices were comprised of
single tree species abundance as well as species groups. Groups were formed according to common ecological species requirements
with respect to shade tolerance, soil moisture and soil nutrients. Though species variance could only be partially explained,
a clear ranking in the relative importance of environmental variables emerged. Tree basal area of formerly cultivated Castanea sativa (Mill.) was the most important factor accounting for up to 50% of species’ variation. Influence of topographic attributes
was minor, restricted to profile curvature, and partly contradictory in response. Our results suggest the importance of biotic
factors and soil properties for small-scale variation in tree species composition and need for further investigations in the
study area on the ecological requirements of tree species in the early growing stage. 相似文献
24.
Fulvio Marsilio Barbara Di Martino Ilaria Meridiani Paolo Bianciardi 《Journal of veterinary diagnostic investigation》2006,18(2):215-217
Fourteen blood samples collected from dogs that were seropositive for Ehrlichia canis were examined for the presence of the citrate synthase gene using a highly specific and sensitive novel polymerase chain reaction assay. The assay detected E. canis DNA in 3 dogs. The complete nucleotide sequence of the citrate synthase gene was determined in 2 of the test-positive samples, and represents the first sequence of the gene to be derived from Italian isolates. The sequence data displayed high identity (99.2%) between the geographically separated Italian samples and the Oklahoma strain of E. canis. The high-sequence conservation revealed by molecular analysis confirmed the usefulness of the citrate synthase gene as a target for detection of E. canis. 相似文献
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Alphey L Beard CB Billingsley P Coetzee M Crisanti A Curtis C Eggleston P Godfray C Hemingway J Jacobs-Lorena M James AA Kafatos FC Mukwaya LG Paton M Powell JR Schneider W Scott TW Sina B Sinden R Sinkins S Spielman A Touré Y Collins FH 《Science (New York, N.Y.)》2002,298(5591):119-121
At a recent workshop, experts discussed the benefits, risks, and research priorities associated with using genetically manipulated insects in the control of vector-borne diseases. 相似文献
26.
Carbonaro M Mattera M Nicoli S Bergamo P Cappelloni M 《Journal of agricultural and food chemistry》2002,50(19):5458-5462
Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and alpha- and gamma-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/alpha-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas alpha-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These data provide evidence that an improvement in the antioxidant defense system of the plant occurred as a consequence of the organic cultivation practice. This is likely to exert protection against damage of fruit when grown in the absence of pesticides. 相似文献
27.
Sina Marsilio Shelley J. Newman James Scot Estep Paula R. Giaretta Jonathan A. Lidbury Emma Warry Andi Flory Paul S. Morley Katy Smoot Erin H. Seeley Matthew J. Powell Jan S. Suchodolski Jörg M. Steiner 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(2):669-677
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选用烟农19、中麦578、伟隆169、华成1688、安农1589、天益科5号、荃麦725、安农0711、西农99、华展199和中育1211共11个适宜皖北地区种植的小麦品种,研究分析了各小麦品种的产量、群体动态变化、干物质转运积累与分配等特性。结果表明,11个供试小麦品种产量均达到7 000 kg·hm-2以上,属高产小麦品种;其中伟隆169、荃麦725、西农99和华展199的产量都达到了8 000 kg·hm-2以上,产量构成协调,穗数及成穗率较高,并且干物质积累量、干物质在籽粒中的分配量以及干物质转运量高于其他品种。相关分析表明,产量与分蘖成穗率呈显著正相关,与穗数呈极显著正相关,伟隆169、荃麦725、西农99和华展199 穗数、分蘖成穗率较高,具有较高产量,适宜皖北地区推广种植。 相似文献
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Marsilio S Kleinschmidt S Harder J Nolte I Hewicker-Trautwein M 《Anatomia, histologia, embryologia》2011,40(1):61-67
In this study, CD3(+) T lymphocytes and IgA(+) , IgG(+) and IgM(+) plasma cells were quantified in the tunica mucosa of the intestinal tract of 12 pet cats without gastrointestinal diseases. The study included full-thickness biopsies of the duodenum, jejunum, ileum and colon. The distribution and quantification of CD3(+) T cells, IgA(+) , IgG(+) and IgM(+) plasma cells within the intestinal tunica mucosa was performed by using immunohistochemical methods and computer-aided morphometry. CD3(+) T cells were significantly prominent in the villi and their numbers increased from duodenum to ileum but decreased towards the colon. The predominant type of plasma cells was IgA(+) cells, followed by IgM(+) cells. The number of IgG(+) cells was generally low compared to the other plasma cell types investigated. The results of the vertical distribution showed that IgA(+) and IgM(+) plasma cells were most numerous in the lower crypt areas, whilst IgG(+) plasma cells accumulated in the upper crypt region with a decline towards the villi and the lower crypt areas of control cats. All types of plasma cells showed a general decline from the duodenum towards the caudal sections of the intestinal tract regarding the horizontal distribution of plasma cells. This study provides a comprehensive overview on the vertical and horizontal distribution and the number of CD3(+) T cells and IgA(+) , IgG(+) and IgM(+) plasma cells in the intestinal tunica mucosa of pet cats. 相似文献
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【目的】 了解并掌握鸭坦布苏病毒(Duck Tembusu virus,DTMUV)流行特点及病毒生物学特性,为DTMUV防治提供理论依据和技术支撑。【方法】 通过细胞及鸡胚接毒试验对河北某鸭场10只具有典型临床症状的发病鸭进行病毒分离,用RT-PCR、透射电镜观察、Western blotting及间接免疫荧光试验(IFA)等方法鉴定,进行动物回归试验测定病毒毒力并对其进行囊膜蛋白遗传进化分析。【结果】 分离到的病毒可在DF-1细胞上稳定增殖产生典型细胞病变效应(CPE)并致死鸡胚;病毒纯化后经电镜观察可见直径30~60 nm的病毒粒子;RT-PCR结果显示,在约270 bp处可见单一条带,与DTMUV预期大小一致;Western blotting结果显示,在60 ku处有特异性条带,与E蛋白大小一致;IFA结果表明,接种病毒的DF-1细胞胞质中可见明亮的特异性荧光,以上结果均表明分离的病毒为DTMUV。将分离到的病毒命名为AX2020株,AX2020株经肌内注射感染北京鸭后感染率高达100%,发病鸭产生神经症状及腹泻等典型临床症状;经序列比对发现AX2020株和GA株(MK907880.1)相似性最高,与SD14毒株(MH748542.1)亲缘关系较远。与商品灭活疫苗毒株HB2010株(MN649262.1)和活疫苗毒株FX2010株(MH414568.1)相比,AX2020株第93、277和487位氨基酸发生了的突变。【结论】 成功分离得到1株DTMUV AX2020株,分离毒株对北京鸭具有较强的致病性,AX2020株的囊膜蛋白与国内疫苗毒株相比,已经发生了氨基酸位点的突变,结果为鸭坦布苏病毒病的流行病学及后续疫苗相关研究奠定了一定的基础。 相似文献